Re: TCL TK
tcl/tk is popular b/c it is portable scripting language commonly found in tools/processing programs. For ex. Xilinx EDA uses it heavily. It is also found in some academic research.
TK is just a simple gui for TCL. if you already know TCL then picking up tk is easy, just look at some of the examples that the tcl/tk document provide.
Sry, i don't have a book for you. But, here is a very good tutorial that i used when i was learning.
Added after 1 minutes:
sry, forgot to paste the link b4 submitting
the link was:
h**p://www.tcl.tk/man/tcl8.5/tutorial/tcltutorial.html
good for syntax and quick overview